P05501 (CYB_SCHPO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Cytochrome b

Alternative name(s):
Complex III subunit 3
Complex III subunit III
Cytochrome b-c1 complex subunit 3
Ubiquinol-cytochrome-c reductase complex cytochrome b subunit

Gene names

Name:	cob
Synonyms:	cytb
ORF Names:	SPMIT.05

Encoded on

Mitochondrion

Organism

Schizosaccharomyces pombe (strain 972 / ATCC 24843) (Fission yeast) [Reference proteome]

Taxonomic identifier

284812 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Fungi › Dikarya › Ascomycota › Taphrinomycotina › Schizosaccharomycetes › Schizosaccharomycetales › Schizosaccharomycetaceae › Schizosaccharomyces › Schizosaccharomyces pombe

Protein attributes

Sequence length	387 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis By similarity.
Cofactor	Binds 2 heme groups non-covalently By similarity.
Subunit structure	Fungal cytochrome b-c1 complex contains 10 subunits; 3 respiratory subunits, 2 core proteins and 5 low-molecular weight proteins. Cytochrome b-c1 complex is a homodimer By similarity.
Subcellular location	Mitochondrion inner membrane; Multi-pass membrane protein By similarity.
Miscellaneous	Heme 1 (or BL or b562) is low-potential and absorbs at about 562 nm, and heme 2 (or BH or b566) is high-potential and absorbs at about 566 nm By similarity.
Sequence similarities	Belongs to the cytochrome b family.

Ontologies

Keywords
Biological process	Electron transport Respiratory chain Transport
Cellular component	Membrane Mitochondrion Mitochondrion inner membrane
Domain	Transmembrane Transmembrane helix
Ligand	Heme Iron Metal-binding
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	mitochondrial electron transport, ubiquinol to cytochrome c Traceable author statement PubMed 6094974. Source: PomBase
Cellular_component	integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW mitochondrial respiratory chain complex III Traceable author statement PubMed 6094974. Source: PomBase
Molecular_function	electron carrier activity Inferred from electronic annotation. Source: InterPro metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW ubiquinol-cytochrome-c reductase activity Traceable author statement PubMed 6094974. Source: PomBase
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 387	387	Cytochrome b		PRO_0000061762
Regions
	Transmembrane	35 – 55	21	Helical; Potential
	Transmembrane	75 – 95	21	Helical; Potential
	Transmembrane	116 – 136	21	Helical; Potential
	Transmembrane	141 – 159	19	Helical; Potential
	Transmembrane	179 – 199	21	Helical; Potential
	Transmembrane	231 – 251	21	Helical; Potential
	Transmembrane	288 – 308	21	Helical; Potential
	Transmembrane	321 – 341	21	Helical; Potential
	Transmembrane	347 – 367	21	Helical; Potential
Sites
	Metal binding	82	1	Iron 1 (heme b562 axial ligand) By similarity
	Metal binding	96	1	Iron 2 (heme b566 axial ligand) By similarity
	Metal binding	183	1	Iron 1 (heme b562 axial ligand) By similarity
	Metal binding	197	1	Iron 2 (heme b566 axial ligand) By similarity

Sequences

	Sequence		Length	Mass (Da)
	P05501 [UniParc]. Last modified December 15, 1998. Version 4. Checksum: 3C6EB9E3E4FC4494	FASTA	387	43,737
	10 20 30 40 50 60 MKILKSNPFL ALANNYMIDA PEPSNISYFW NFGSLLACVL VIQIVIGILL ACFYIPNMDL 70 80 90 100 110 120 AFLSVERIVR DVNYGFLLRA FHANGASFFF IFLYLHIGRG LYYGSYKYPR TMTWNIGVII 130 140 150 160 170 180 FLLTIITAFL GYCLPANQMS FWGATVITNL LSAVPFIGDD LVHLLWGGFS VSNPTLNRFF 190 200 210 220 230 240 SLHYLMPFVI AALSVMHLIA LHTNGSSNPL GVTANMDRIP MNPYYLIKDL ITIFIFLIGI 250 260 270 280 290 300 NYMAFYNPYG FMEPDCALPA DPLKTPMSIV PEWYLLPFYA ILRAIPNFQL GVIAMLLSIL 310 320 330 340 350 360 VLLLLPLLDF SAIRGNSFNP FGKFFFWTFV ADFVILAWIG GSHPENVFIT IGAIATIFYF 370 380 SYFFILIPVY TILGNTLIDL NLSSIKR

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The mitochondrial genome of the fission yeast Schizosaccharomyces pombe. The cytochrome b gene has an intron closely related to the first two introns in the Saccharomyces cerevisiae cox1 gene." Lang B.F., Ahne F., Bonen L. J. Mol. Biol. 184:353-366(1985) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: AD7-50.
[2]	"The mitochondrial genome of Schizosaccharomyces pombe." Lang B.F. (In) O'Brien S.J. (eds.); Genetic Maps (6th edition), pp.3118-3119, Cold Spring Harbor Laboratory Press, New York (1993) Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: AD7-50.

Cross-references

Sequence databases
EMBL GenBank DDBJ	X02819 Genomic DNA. Translation: CAA26588.1. X54421 Genomic DNA. Translation: CAA38287.1. Sequence problems.
RefSeq	NP_039502.1. NC_001326.1.
3D structure databases
ProteinModelPortal	P05501.
SMR	P05501. Positions 1-380.
ModBase	Search...
Protein-protein interaction databases
STRING	4896.SPMIT.05-1.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
EnsemblFungi	SPMIT.05.1; SPMIT.05.1:pep; SPMIT.05.
GeneID	1669523.
KEGG	spo:ScpofMp04.
Organism-specific databases
PomBase	SPMIT.05.
Phylogenomic databases
HOGENOM	HOG000255206.
KO	K00412.
OrthoDB	EOG444PTX.
Family and domain databases
InterPro	IPR016175. Cyt_b/b6. IPR005798. Cyt_b/b6_C. IPR005797. Cyt_b/b6_N. IPR016174. Di-haem_cyt_TM. [Graphical view]
PANTHER	PTHR19271. PTHR19271. 1 hit.
Pfam	PF00032. Cytochrom_B_C. 1 hit. PF13631. Cytochrom_B_N_2. 1 hit. [Graphical view]
SUPFAM	SSF81648. Cytochrome_b/b6_C. 1 hit. SSF81342. Transmembr_di-haem_cytochrome. 1 hit.
PROSITE	PS51003. CYTB_CTER. 1 hit. PS51002. CYTB_NTER. 1 hit. [Graphical view]
ProtoNet	Search...
Other
NextBio	20797079.

Entry information

Entry name

CYB_SCHPO

Accession

Primary (citable) accession number: P05501

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1988
Last sequence update:	December 15, 1998
Last modified:	May 1, 2013
This is version 100 of the entry and version 4 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Fungal Protein Annotation Program